2 AimTo give you an understanding of the principles of screening and identify risk factors for cardiovascular disease

3 Objectives Discuss and explore the criteria for screeningHave an understanding of cardiovascular diseaseLook at the policies in Wales that drive screening for cardiovascular diseaseDiscuss cardiovascular disease prevention, risk assessment and the tools used.Identify the risk factors for cardiovascular diseaseHow to use a risk assessment tool

4 What is Screening?‘Screening is a public health service in which members of a defined population, who do not already perceive themselves to be at risk of, or are already affected by a disease or its complications, are asked a question or offered a test, to identify those individuals who are more likely to be helped than harmed by further tests or treatment to reduce the risk of a disease or its complications’ (UK National Screening Committee 2000)

5 What is Screening?Screening is a process of identifying apparently healthy people who may be at increased risk of a disease or condition. They can then be offered information, further tests and appropriate treatment to reduce their risk and/or any complications arising from the disease or condition.

6 The NSC Criteria for ScreeningThe condition should pose an important health problemThe natural history of the condition should be understoodThere must be a safe and validated test or examinationTreatment of the disease at an early stage should be beneficialThe screening programme must reduce mortality and morbidityThe test must be acceptable to the populationThe programme must provide value for money

8 Extended ScreeningSince original criteria were developed the breadth of screening has extended to include risk factors (eg. blood pressure or cholesterol) or susceptibility for disease (eg. genetic markers for cancer or HIV status).

9 Limitations of ScreeningCan reduce the risk of developing a condition but cannot offer a guarantee of protection.Screening is therefore increasingly presented as RISK REDUCTIONAlthough may benefit populations, not all participants will benefit and some may even be harmed.HARM?DISCUSS Harm – anxiety; complications, unnecessary investigations, discomfort

10 Intention of screeningTo identify disease in a community who do not have symptoms, early in the disease process so that intervention and management can hopefully reduce mortality and suffering from the disease.

11 Remember Screening has the potential to cause harmBenefits must outweigh the harmInformed consent is very importantInclusion should be voluntaryPeople do not have symptomsQuality assuranceBecause screening is voluntary, asymptomatic & has the potential to cause harm the service has to be of a high standard – Quality assurance

12 What is Cardiovascular Disease?‘Disease of the heart and blood vessels’Also known as Coronary Heart Disease (CHD) and Ischaemic Disease.(Cardiac Disease NSF for Wales, 2009)

13 CVD cont.Narrowing of the arteries that supply the heart and is due to a gradual build up of fatty material called atheroma.The narrowing can cause myocardial infarction, angina and other forms of chronic heart disease.Other forms of CVD include stroke, transient ischaemic attack and peripheral vascular disease.

15 Cardiovascular Disease (CVD)CVD is the main cause of death in the UK accounting for over 216,000 deaths in 2004: around 4 out of every 10 deaths. The main forms of CVD are coronary heart disease (CHD) and strokeCHD accounts for approx 50% of CVD deathsStroke accounts for approx 25% of CVD deathsCVD is one of the main causes of premature death: 32% in men and 24% in women(BHF, 2006)

16 Cardiovascular Disease (CVD)CHD causes over 105,000 deaths a year in the UK:approx 21% deaths in menapprox15% deaths in womenThis compares to around 33,000 deaths a year from lung cancer, 16,000 deaths from colorectal cancer and 12,000 deaths from breast cancer.(BHF, 2006)

17 Cardiovascular DiseaseAround 230,000 people in the UK suffer a heart attack each yearIn around 30% of heart attacks the patient diesDeath rates from CHD have been falling in the UK since the late 1970’s; for adults under 65yrs they have fallen by over 44% in the last 10 yearsWhereas mortality from CHD is falling rapidly, morbidity from CHD and other circulatory disease appears to be rising, especially in older age groups.(BHF, 2006)

18 Economic CostsCHD causes health care system in UK around £3.5 million a yearHospital care for CHD patients accounts for 79% of these costsbuying and dispensing drugs accounts for a further 16%.Primary Prevention and Primary Care 4%(BHF, 2006)Looking only at the costs of CHD to the health care system under estimates the total cost of CHDCHD also costs the UK economy about £4,4000 million because of days lost due to death, illness and informal care of people with the disease. In total costs the economy about £7, 9000 million a year

19 Policies in Wales that drive screening for cardiovascular diseaseRevisit the criteria for screening

20 Review of Health and Social Care in Wales (2003)Builds on the Wanless Report and Identifies that services need to be realigned to focus on prevention and early intervention

21 Designed for Life (2003)Sets the direction and requirements for the NHS describes the kind of health and social care services the people of Wales can expect by 2015Improve health and reduce ill health and where possible eliminate inequalities in healthSupport the role of people in promoting their health individually and collectivelyProvide quality assured clinical treatment and care appropriate to need and based on evidence

22 The Cardiac Disease National Service Framework (NSF) for Wales (WAG 2009)Everyone at high risk of developing coronary heart disease and all those who have been diagnosed as having the disease should have access to a multi factorial risk assessment and be offered an appropriate treatment plan.Key document that updates the Coronary Heart Disease NSF 2001Builds on previous polices & documents

23 Health Evidence Bulletin: CHDSummarizes the best current evidence to support the development of guidelines and care pathways at national and local levelsDevelop, implement and monitor evidence based programmes to address tobacco use, diet and physical activity, targeted at the most disadvantaged communities in Wales.

24 The NSF for CHDEveryone who may be at risk of developing CVD is to be offered a risk assessment.All those found to be at high risk together with those who have established CHD, occlusive arterial disease, diabetes or familial hypercholesterolaemia, are offered lifestyle advice and appropriate treatment.

26 Prevention of CVDPrimary prevention aims to prevent the development of CVD in high risk individualsSecondary prevention aims to prevent further events in those patients with established CVD

27 How do we assess risks? CVD Risk Assessment Tools Based on researchThey identify high-risk people for primary preventionThey are an aid to making a clinical decisionUsually based on groups of people with untreated levels of blood pressure and cholesterol levels.There are limitations to all the risk toolsThey can under estimate risk in people with a family history of CVD and certain high risk ethnic groupsHow do we assessWhy do we assess

29 Joint British Societies Coronary Risk Prediction Chart (JBS2)Was considered the most accurate and preferred method for estimating CVD risk for different societies.Not appropriate for people with established CVD, familial high cholesterol, chronic renal dysfunction or diabetes.Estimates the absolute 10 year risk of developing CVDBased on the Framingham Heart Study.British Cardiac Society, BHS, Diabetes UK, HEART UK, Primary Care Cardiovascular Society, The Stroke Association

30 Framingham Heart StudyBegan in 1948.More than residents of Framingham, Massachusetts, USA.Collected data on blood pressure, diabetic status, smoking and causes of death.People with pre-existing disease were excludedThis data was used to define the risk factors for CVD.This study is ongoing

33 Modifiable Risk FactorsSmokingPoor dietLack of physical exerciseRegular excessive alcohol consumptionAbdominal obesityHypertensionDiabetesDyslipidaemiaThe good news is that the effects of many risk factors can be changed. You can not change the risk factor only its effects. The effects can be reduced by making lifestyle changes

35 Who should have a CVD risk assessment?All adults aged over 40 years or moreAdults of any age who have;A strong family history of early CVDA 1st degree relative with a hereditary cholesterol disorder1st degree relative = parent; brother; sister; child.People with existing cardiovascular disease and/or diabetes do not need to be assessed as they are already known to be high risk

37 Measurement of ObesityThere are various ways in which to measure different aspects of obesity. They include Body Mass Index (BMI), skin fold thickness, waist circumference, waist to hip ratio and bio-impedance.Body Mass Index (BMI)The most common method of measuring obesity is the Body Mass Index (BMI). BMI is calculated by dividing body weight (kilograms) by height (metres) squared.BMI is the most widely used approach in the UK, but it is important to note that it is not a direct measure of body fat mass or distribution, and BMI measures may be skewed by very high muscle mass. The relationship between BMI and health also varies with ethnicity.In children and adolescents BMI varies with age and sex, for this reason a growth reference must be used.

40 Skin fold thicknessSkin fold thickness refers to the measurement of subcutaneous fat located directly beneath the skin by grasping a fold of skin and subcutaneous fat and measuring it using calipers. It is used mainly to determine relative fatness and the percentage of body fat. Measurement requires callipers and some basic training.Waist circumference and waist to hip ratioThe circumference of the waist is sometimes used as a simple measure of body fatness, though it can be subject to measurement error. Adult waist circumference cut points are:Increased risk of health problems: Men≥ 94cm Women ≥ 80cmGreatly increased risk of health problems: Men ≥ 102cm Women ≥ 88cmWaist to hip ratio examines fat distribution and in practice is used less frequently, given the established links between waist circumference alone and health risk.Bio-impedanceThis measures the impedance or opposition to the flow of a very small electric current as it passes through the body. As lean mass is made up of 73% water and fat has no water content, this method estimates lean tissue mass (which acts as a conductor) and fat mass (which acts as an insulator), through changes in voltage. Home machines are available for bio-impedance measurement though these can be inaccurate as they often estimate from the legs only.

48 Case Study 1Mrs Lewis is a 42 year old lady, non – smoker , with a blood pressure of 120/70 and a cholesterol of 3.9 mmol/l.What is this lady’s current risk ?

49 Case Study 2A 52 year old male who is currently smoking 20 cigarettes a day, has a systolic blood pressure of 158mmHg and a non fasting cholesterol of 7.0mmol/l.What is his 10 year risk of a CVD event?3 months later, he has stopped smoking his systolic blood pressure is 140 and his cholesterol remains 7.0mmol/l.Has his risk changed ?

50 Case study 3A 50 year old woman who is a non-smoker, does not have diabetes, and has a blood pressure of 120/80 and a total cholesterol of 8.2mmol/l.What is this woman’s current level of risk?How would that risk change if she then told you that her father died aged 45 years of an MI?